Fedora and OVS Bridge Interfaces

I run OpenStack on my laptop, and I’ve been chasing down a pernicious
problem with OVS bridge interfaces under both F19 and F20. My
OpenStack environment relies on an OVS bridge device named br-ex for
external connectivity and for making services available to OpenStack
instances, but after rebooting, br-ex was consistently unconfigured,
which caused a variety of problems.

This returns failure (=1) if the interface flags contain ,UP.
Unfortunately, since information about this device is stored
persistently in ovsdb, the device is already UP when ifup is
called, which causes ifup-ovs to skip further device
configuration. The logic that calls check_device_down looks like
this: